Micromechanical hinged elements have been used to form many different types of micromechanical and microelectromechanical devices (see e.g. U.S. Pat. Nos. 6,300,156; 6,543,087; 6,903,861; and 6,675,671 which are incorporated herein by reference). Many different approaches have been used to unfold micromechanical hinged elements which can have lateral dimensions of up to a few millimeters. These approaches include using forces due to gravity, surface tension or magnetism to erect a plurality of three-dimensional structures which are generally batch-fabricated on a common substrate. Additionally, mechanical forces provided by a micromanipulator probe can be used to contact and erect each micromechanical structure one at a time, but this individualized assembly approach is generally not preferred for volume production.
What is needed for many applications is a way of precisely raising a micromechanical structure to an arbitrary angle with respect to a supporting substrate.
The present invention provides a solution to this problem by providing an active hinge apparatus which can be operated using an actuator provided on the substrate.
The active hinge apparatus of the present invention is relatively compact and can be fabricated by conventional surface micromachining.
The active hinge apparatus of the present invention can be connected to a plate, micromirror or any other type of micromechanical structure to be raised above a substrate, with the active hinge apparatus being operated by an electrostatic actuator, a thermal actuator, or a manually-operated actuator connected thereto.
These and other advantages of the present invention will become evident to those skilled in the art.